1. Field of the Invention
This invention generally relates to laser scanning systems for reading coded indicia, such as bar code symbols, and, more particularly, to a hand-held laser scanning head having an on-board keyboard, an on-board display, an on-board printer and an on-board radio transceiver, preferably using spread spectrum technology to enable the head to communicate electronically to and from a remote site.
2. Description of the Related Art
Various optical readers and optical scanning systems have been developed heretofore for reading bar code symbols appearing on a label or on the surface of an article. The bar code symbol itself is a coded pattern of indicia comprised of a series of bars of various widths spaced apart from one another to bound spaces of various widths, the bars and spaces having different light-reflecting characteristics. The readers and scanning systems electro-optically decode the symbol to multiple alpha-numerical characters that are intended to be descriptive of the article or some characteristic thereof. Such characters are typically represented in digital form as an input to a data processing system for applications in point-of-sale processing, inventory control, and the like. Scanning systems of this general type have been disclosed, for example, in U.S. Pat. Nos. 4,251,798; 4,360,798; 4,369,361 and 4,387,297, all of which have been assigned to the same assignee as the instant application.
It is generally known to emit light beam from a hand-held, portable scanning head supported by an operator, and to aim the head and, more particularly, the light beam, at a symbol to be read. The light beam is preferably a laser beam generated by a gas or semiconductor laser source. An optical train directs the laser beam along a light path, and focuses the laser beam to a scan spot at a reference plane, typically located remotely from the head. At least a portion of the laser beam reflected off the symbol located in the vicinity of the reference plane is collected and detected over a field of view by a sensor on-board the head. A scanning component sweeps either the scan spot in a scan across the symbol, or sweeps the field of view. The sensor generates electrical analog signals indicative of the symbol. The analog signals are converted into digital signals, and then decoded into data representative of the symbol, and thereupon, conducted to a remote site such as a host computer, for further processing. Reading of the symbol is initiated by a manually actuatable trigger. The system determines when the symbol has been successfully decoded and read, and then automatically terminates the reading.
Keyboards for manual data entry are useful components in such systems. Keyboards comprised of multiple keys require a great deal of space, and are typically mounted remotely from the head, or are mounted on the head but a location awkward for the operator. If the keyboard was mounted on the barrel or body portion of the head in front of a window through which the outgoing light beam passes, the operator's fingers and hand would intercept the outgoing light beam in the event the operator worked the keyboard during symbol reading. If the window allowed reflected light to pass therethrough en route to the sensor, then the operator's fingers and hand would also block that reflected light, again interfering with the reading operation. The keyboard could also be mounted on a terminal unit that is detachably mounted on a handle of the head.
Displays for displaying information are also useful components in such systems. Typically, indicator lights are used as displays to signal the operator. When displays are fashioned as one or more screens, they occupy a great deal of space. This is not a problem for contact devices of the type disclosed in U.S. Pat. No. 4,251,798, where space is available, but is a problem for hand-held, non-contact-type scanning heads where available space is at a premium. Often, such displays are mounted on separate terminal units mounted remotely from, or attachable to, the head.
The art proposed in U.S. Pat. No. 4,628,193 mounting a keyboard, a display and a printer on a hand-held electronic apparatus in connection with a parcel delivery service, a hospital medication program and a blood sample identification system.